README file for IBM Informix Database Driver for Perl DBI Version 2013.0118 (2013-01-18)
You may distribute under the terms of either the GNU General Public
License or the Artistic License, as specified in the Perl README file.
Be aware that URLs and mailing list addresses can change after a
product is released but before the next version of the product is made
available to the public.
The primary URL for information about Perl, DBI and DBD::Informix is
http://dbi.perl.org/
The primary email address for direct assistance with DBD::Informix is
dbd.informix@gmail.com, but don't use it until you've read the notes
below.
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PREREQUISITES
You need the following five items to build IBM Informix Database Driver for Perl DBI:
1. Perl 5.6.1 or later.
2. DBI 1.38 or later.
3. A C compiler that accepts function prototypes (such as GCC).
4. Informix ESQL/C 5.20 or later, or Client SDK 3.00 or later.
5. A 'stores' database to which you can connect without specifying
username or password and in which you can create tables. Ideally,
the connection should not use shared memory (neither olipcshm nor
onipcshm), and you should have DBA privileges in the database.
The basic build steps are:
perl Makefile.PL
make
make test
make install
If you are not sure about any of these items or if one of the build
steps above fails when you run it, you need to read the information
below. Read the BUILD AND TEST ENVIRONMENT section when you set your
environment variables. If you run into problems during the build or
test phases, read the section IF YOU HAVE PROBLEMS BUILDING
DBD::INFORMIX. Also check the Announce file to see whether there is
any extra information in there.
When you have DBD::Informix working *and* installed, use the ItWorks
Perl script (previously a shell script) to report your successful
installation. Be sure to review the output (especially the email
address it deduces), and send it in an email with the subject
"DBD::Informix - It Works" to dbd.informix@gmail.com.
TECHNICAL SUPPORT
For information on Informix Technical Support, please run:
perldoc DBD::Informix::TechSupport
If you have not installed DBD::Informix, inspect the file
DBD/Informix/TechSupport.pm in the source directory.
MAILING LIST SUPPORT FOR DBI AND DBD::INFORMIX
The mailing list for Perl DBI and DBD::Informix is dbi-users@perl.org.
For information on how to subscribe to (and unsubscribe from) the
dbi-users mailing list, send a message to dbi-users-help@perl.org. You
could also consider using the news groups comp.lang.perl.modules (for
Perl and DBI) and comp.databases.informix (for DBD::Informix).
Before sending anything to any of these, you need a very good excuse
for not reporting the complete environment via the BugReport script.
About 95% of problems can be diagnosed by the information this script
provides - do not assume that you are part of the stray 5%. The script
protects the passwords set for testing DBD::Informix.
perl -Ilib BugReport
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PERL
If you do not have Perl Version 5.6.1 or later installed, you must
build, test, and install it before you do anything else. You should
really use Perl 5.10.0 (ideally, 5.14.0 or later). If at all
possible, use the C compiler to create shared libraries even if the
Perl configuration script suggests that you use the 'ld' program
directly. People who do not use the C compiler to create the shared
libraries have often had many problems, and those who use it have
generally had very few. Note, there are some platforms, including
AIX, where you cannot use the C compiler to create shared libraries,
but that doesn't automatically stop the build from working.
However, in our experience, you are more likely to run into problems
on such platforms than on platforms where you can use the C compiler
to build the shared libraries. Note that DBD::Informix will witter
if you do not use the C compiler to link shared libraries.
Note also that to install DBD::Informix, you must be able to put files
under the Perl lib directory. For alternative options, see the
Notes/nonroot.install file.
If you are working on NT, you should use the Perl binaries available
from ActiveState at http://www.activestate.com. This site also
provides pre-compiled versions of many Perl modules, including DBI (but
not DBD::Informix at 2000-02-01).
DBI
If you do not have DBI version 1.38 or later installed, you should
build, test, and install it. Some older versions of DBD::Informix
allowed you to use older versions of DBI than the version it was
developed with, but the current versions of DBD::Informix do not.
Note that "perl -MCPAN -e 'install Bundle::DBI'" gets the latest
version of DBI and any pre-requisite modules.
C COMPILER
To build DBD::Informix, the C compiler must accept function prototypes.
This is not a problem on any computer to which Informix is currently
ported (though the HP-UX bundled compiler does not accept prototypes at
all, and the ANSI compiler does not accept them unless told to do so).
If you have problems, get the GNU C Compiler, Version 2.95.2 or later.
It is available from http://gcc.gnu.org/ and many mirror sites around
the world. You must use the same compiler to build Perl, DBI, and
DBD::Informix. The Notes/hpux file contains information about how to
compile the GNU C Compiler on HP-UX.
ESQL/C OR CLIENT SDK
You must have a version of IBM Informix Client SDK installed on the
computer where you wish to compile DBD::Informix. IBM Informix Connect
is not sufficient for compiling DBD::Informix. The Notes/FAQ file
contains more information about what you need. ESQL/C Versions 4.1x
and earlier are not (and will not be) supported by DBD::Informix.
ESQL/C Versions 5.00 and up should be OK. If you do not have ESQL/C,
DBD::Informix will not work. You can download IBM Informix Client SDK
for free from the Informix evaluation web site:
http://www.ibm.com/software/data/informix/downloads.html
If you have IBM Informix ODBC drivers available to you, you can
consider using DBD::ODBC instead. If you are on Linux, you should
investigate the software available from the following IBM Informix web
sites:
http://www.ibm.com/software/data/informix
http://www.ibm.com/software/data/developer/informix
You must also be able to compile, link, and run ESQL/C programs with
your setup. Makefile.PL will test that you can do this, but you can
save time if you ensure this beforehand. If you cannot compile, link
and run free-standing ESQL/C programs, you certainly cannot link
DBD::Informix into Perl. For help with environment variable settings,
consult the information below and also the Notes/environment.variables
file. (If you are not yet familiar with how to set environment
variables, be sure to get and read a UNIX primer such as "Learning the
Unix System, 4th Edition" from O'Reilly, http://www.oreilly.com/, and
be prepared for a major learning exercise).
DBD::Informix, Version 1.00 and later, provides limited support for
user-defined data types (UDTs), treating them as CHAR(255). To handle
BLOB and CLOB values, use LOTOFILE() when you fetch the data and
FILETOBLOB() or FILETOCLOB() when you insert data - see t/t91udts.t for
examples. To handle nonblob UDTs that exceed 255 characters in length,
use server-side cast to lvarchar, as in
select mycol::lvarchar from mytab;
Note that the tests that create tables with BLOB or CLOB columns will
place them in the smart blob space designated by DBD_INFORMIX_SBSPACE,
and will use the default value 'sbspace' if you do not specify an
alternative. If you do not have any smart blob spaces, the tests will
fail unless you set DBD_INFORMIX_NO_SBSPACE.
Most versions of ESQL/C that support shared libraries have shared
linking as the default, which is correct. Other versions reportedly
have static linking as the default, which is a nuisance. The
Makefile.PL will add the '-shared' flag to the ESQL/C command line to
try to force shared libraries for ESQL/C Versions 7.20 and up. If this
does not work for you or if you are building a static Perl, you will
need to set the environment variable DBD_INFORMIX_ESQLC_LINKAGE either
to nothing if your version of ESQL/C does not support the '-shared'
option or to '-static' to force static linkage. You could also use
this environment variable to bootstrap any special ESQL/C compiler
options into the build process (such as '-thread' if you experiment
with threaded Perl and threaded ESQL/C); you are advised to set
'-static' or '-shared' as well.
STORES DATABASE
Unless you have a 'stores' database that you can connect to without
specifying a username or password (and in which you can create tables),
you will need to set various environment variables to tell the build
and test code for DBD::Informix which database to use for testing and
exactly how to connect to it. For more details on the environment
variables that you can set, see the BUILD AND TEST ENVIRONMENT section.
You *must* have a fully working Informix environment before you try to
build and test DBD::Informix. This means you must have access to at
least one database. Ideally, you should have at least RESOURCE level
privileges (or DBA privileges) on that database; if you don't and
cannot obtain privileges on a database (perhaps by creating one), then
set DBD_INFORMIX_NO_RESOURCE=yes in your environment. Ideally, you
should be able to create databases too; if you cannot do so, then set
DBD_INFORMIX_NO_DBCREATE=yes in your environment. If you do not
understand what this means, refer to the "Informix Guide to SQL:
Syntax" manual and read the discussion of the GRANT statement. You can
obtain a PDF version of any Informix manual from:
http://www.ibm.com/software/data/informix/pubs/library
If you do not have RESOURCE (preferably DBA) privileges on a database,
consider creating a database called 'stores' for testing. If you do
not have DBA privileges, the test t/t55mdata.t may fail but, unless you
have other problems, you can disregard this failure.
Note that the tests for DBD::Informix create and drop their own tables.
Most of the tests use temporary tables. It does not matter whether the
test database has database logging, though a logged database allows
more features to be tested than an unlogged database. You can use a
brand new, empty database for testing. When DBD::Informix creates any
database object, the name begins with "dbd_ix_". After running the
test t/t99clean.t, nothing should remain from the testing. If you find
any leftovers, report them to the maintenance team. DBD::Informix has
one test that creates a database and then drops it.
SHARED MEMORY CONNECTIONS
The multiple connection tests use two databases for preference (though
the tests will use the same database twice if you do not specify two
separate databases). As of version 0.95, the esqltest program will
report that both connections use shared memory and will allow you to
proceed after writing a message. The actual test scripts attempt to
detect that the two connections both use shared memory connections and
skip the tests. However, if you run into problems with shared memory
connections (for example, error -27000 from the esqltest program),
read Notes/olipcshm. If your databases are not on the computer where
you build DBD::Informix, be sure that you have the necessary privileges
the necessary privileges to connect to the machine where the databases
are. This may be as simple as setting DBD_INFORMIX_USERNAME and
DBD_INFORMIX_PASSWORD (see BUILD AND TEST ENVIRONMENT) or might require
you to get your system administrators to set up a login account for you
on the computer.
BUILD AND TEST ENVIRONMENT
Be sure to set $INFORMIXDIR even if the software is installed in
/usr/informix and to have $INFORMIXDIR/bin on your PATH. The build no
longer works unless these environment variables are set. Also, if you
are using ESQL/C version 6.x or later, you may be using ESQL/C shared
libraries which are found in the directories $INFORMIXDIR/lib and
$INFORMIXDIR/lib/esql. With Version 0.95 and above, the absolute
pathnames of the Informix shared libraries will be built into your
DBD::Informix library by default, which means that you do not need to
worry about LD_LIBRARY_PATH, LD_RUN_PATH, SHLIB_PATH, or LIBPATH at
runtime. The downside of using absolute pathnames is that if you move
your Informix software, you also need to rebuild and reinstall
DBD::Informix.
If rebuilding DBD::Informix is unacceptable, you need to set the
environment variable DBD_INFORMIX_RELOCATABLE_INFORMIXDIR to a value
such as "yes". The library will be built using relative names to
identify the Informix shared libraries. You will be warned that this
is happening. Both at test time and at run time, you need to ensure
that the Informix shared libraries will be found when you run Perl with
DBD::Informix. On SVR4 and Linux computers, this means adding these
directories to LD_LIBRARY_PATH; on HP-UX, the variable is SHLIB_PATH;
other systems may have other variable names. Note that web servers, in
particular, do not propagate most environment variables unless you tell
them to do so (use SetEnv or PassEnv in Apache). You need to set
INFORMIXSERVER correctly unless you are using version 5.x ESQL/C. You
may need to set other Informix environment variables too. Consult the
Informix documentation and the Notes/environment.variables file.
The documentation available from 'perldoc DBD::Informix::TestHarness'
tells you how to set the DBD_INFORMIX_DATABASE, DBD_INFORMIX_USERNAME,
and DBD_INFORMIX_PASSWORD environment variables for your system. The
parallel environment variables with suffix 2 (DBD_INFORMIX_DATABASE2,
DBD_INFORMIX_USERNAME2, DBD_INFORMIX_PASSWORD2) specify the second test
database completely independently of the first. If the defaults are
OK, you do not have to set any of these six environment variables. The
default database is 'stores'; no username and password are supplied if
none is specified. If you set the username, you must also set the
password to have any effect. Although the testing does as little
damage as possible, it is not a good idea to use the production
database for this. The stores database is a good bet. Note that these
variables have significance only when you run the DBD::Informix tests.
These variables are not used by DBD::Informix itself, only by the code
in DBD::Informix::TestHarness. Ideally, you should set the variables
before you start the build and you should not change them until after
you complete the testing. If you do change them, you should check that
the esqltest program run by 'perl Makefile.PL' still gives your new
environment a clean bill of health.
One step in the setup process tests that you have permissions on the
databases that will be used by the testing. The step compiles and runs
a relatively simple ESQL/C program that opens a few databases, creates
and drops some tables, and exits. If the test fails, you do you do not
get a Makefile so you cannot build DBD::Informix.
Note that if you set the DELIMIDENT environment variable, some tests
will fail, notably t/t56tabinfo.t and t57tables.t.
If your database is IDS 9.x or later then you need:
- either a smart blob space called sbspace,
- or set the environment variable DBD_INFORMIX_SBSPACE to the name of a
smart blob space,
- or set the environment variable DBD_INFORMIX_NO_SBSPACE to 1 to
indicate that smart blob testing should be omitted.
- or let the tests deduce whether the smart blob space is available.
BUILDING DBD::INFORMIX WITH BUNDLES
If you have preconfigured the Perl CPAN module and correctly set up
your Informix environment, you can install DBD::Informix simply
DBD::Informix by simply typing:
perl -MCPAN -e 'install Bundle::DBD::Informix'
This command gets the latest version of DBI (and its prerequisite
modules) and the latest version of DBD::Informix, and compiles, tests,
and install them all completely automatically. Before doing this, you
need to be confident that things will work correctly (or that you've
got good backups of your Perl installation). On the other hand, it is
an extremely convenient method of updating your Perl software.
When you first use the CPAN module, it will ask you many questions,
including the name of the CPAN site from which to download the
material, but the CPAN module saves this information for the next time
and offers you a choice of sites based on continent and
First consider installing the latest CPAN bundle:
perl -MCPAN -e 'install Bundle::CPAN'
BUILDING DBD::Informix
After you install Perl, DBI, and ESQL/C, run:
perl Makefile.PL
The script tries to work out how to build the module. Then run:
make
The make command should run without errors and ideally without warnings
either. If you get warnings, let us know what they are and how they
how they could be fixed generically. If it fails horribly, see below.
Do NOT hand edit the generated Makefile unless you are completely sure
you understand the implications and are willing to make those changes
manually every time the Makefile is regenerated! To make changes,
always try to edit Makefile.PL, which is extensively annotated. Also
refer to should also read the section on ExtUtils::MakeMaker in the 2nd
Edition of 'Programming Perl'.
You should never need to make any changes to the generated Makefile,
nor to Makefile.PL. If you do, *let us know* so that we can try
to make it automatic in a later release.
Then run:
make test
Note that testing DBD::Informix does create some database objects
(tables, views, synonyms, types, etc). The database is called
'dbd_ix_db', and the other object names start with 'dbd_ix_'. Some of
the tables are permanent; most are temporary. The tests are designed
to work whether the tables and database are present when the tests
start or not; that means they get dropped. Do not run the tests if you
have precious tables or databases that begin 'dbd_ix_'! Starting with
DBD::Informix Version 0.61, the cleanup script t/t99clean.t is run at
the end of the testing. It removes the tables, views, synonyms, etc
and so on that DBD::Informix might have created. Running it manually
("test.one.sh t/t99clean.t") also cleans up the database objects
created by testing DBD::Informix. The tests should be 100% clean if
you run the cleanup script, but if you don't run that, the tests can
leave the odd table or stored procedure (or user-defined data types and
so on) in the database.
Additionally, for a really thorough scrutiny of DBD::Informix, you need
to test it with at least three different databases: one created with
MODE ANSI, one created with a transaction log but not MODE ANSI, and
one created without any transaction logs at all:
DBD_INFORMIX_DATABASE=mode_ansi make test
DBD_INFORMIX_DATABASE=logged make test
DBD_INFORMIX_DATABASE=unlogged make test
Different tests will be skipped depending on the version of ESQL/C, the
version of the database, and the logging modes of the databases you are
connecting to.
If you are concerned about both OnLine and SE, then the connection
tests will use two different databases if you set the environment
variable DBD_INFORMIX_DATABASE2 (and possibly DBD_INFORMIX_USERNAME2
and DBD_INFORMIX_PASSWORD2). You can also use one SE database and one
OnLine database. You can also test with different server versions (eg
using 7.2x ESQL/C to connect to a 5.0x OnLine) if you have the software
available.
Once you are satisfied that DBD::Informix is working correctly, you
should install it:
make install
If you ever need to remove it, possibly as a preamble to installing a
new version, you should use the old version's makefile and run:
make uninstall
You can then use the makefile of the new version to install. It is
important to use the correct old or new makefile because the installed
may be different, and if some file is made obsolete by the new version
(is not used by the new version), its makefile will not uninstall the
obsolete file; over time and multiple versions, this could, eventually,
fill your disk completely.
If you run into problems that suggest that the ESQL/C you have will not
work as dynamically loaded libraries (such as on HP-UX or SCO), you
should create a statically linked version of Perl with DBD::Informix
linked to it. Use:
make perl
make test_static
Please consult the Notes/Working.Versions file for information about
known working versions of the software (and specific problem versions).
If you are using a combination of versions which is different from any
previously recorded, please send me (jleffler@us.ibm.com) the details
for your new, successful port.
If you run into major problems even getting the esqltest program to
compile, you can try to compile the esqlbasic.ec program with a plain
ESQL/C command:
esql -o esqlbasic esqlbasic.ec
If even this command will not compile, concentrate on fixing your ESQL/C
ESQL/C environment before doing anything else with DBD::Informix. If
it compiles but does not run, then you need to ensure that you fix the
Informix environment so that you can access databases. Once this test
both compiles and runs, you will probably be able to compile and test
DBD::Informix.
To suppress the esqltest code in Makefile.PL, you can set
DBD_INFORMIX_NO_ESQLTEST=yes in your environment before you run 'perl
Makefile.PL'. If you do that, however, no problem reports will be
accepted; the esqltest code is critical to ensuring that DBD::Informix
has some chance of compiling successfully.
You can see how the esqltest code is compiled if you set
DBD_INFORMIX_DEBUG_ESQLTEST=yes in your environment before you run
'perl Makefile.PL'.
For more information on environment variables for both DBD:Informix and
Informix, see the Notes/environment.variables file.
KNOWN PROBLEMS:
* If you run into problems with spurious options being passed to the
compiler, you can set $DBD_INFORMIX_ESQLCC_REMOVE_OPTIONS_REGEX to
remove those options. For example, if the -KPIC option is being
passed to GCC, set the value of the environment variable to
'^-KPIC$'.
* If you run into problems with spurious options being passed to the
linker, you can set $DBD_INFORMIX_ESQLLD_REMOVE_OPTIONS_REGEX to
remove those options. For example, if the -lc, -laio and -lelf
libraries cause trouble (or are simply redundant), set the value of
the environment variable to '^-l(c|aio|elf)$'.
* If you run into problems with esqlcc or esqlld, set either
DBD_INFORMIX_DEBUG_ESQLLD or DBD_INFORMIX_DEBUG_ESQLCC (or both) to a
non-zero, non-empty value such as 'yes' and rerun the build.
IF YOU HAVE PROBLEMS BUILDING DBD::INFORMIX
Read all this README file (there is a lot of information in here), and
the Notes/bug.reports file, which describes what to do and where to
send the failure report. Please ensure that any email message has
DBD::Informix in the subject line -- thanks!
IF YOU HAVE PROBLEMS USING DBD::INFORMIX
If you have a problem with your own code and all the DBD::Informix
tests succeed, in your initial message give the version information
(see the Notes/bug.reports file), a description of the problem, a
minimal test script, and the results of running the test script on your
machine, along with an explanation of why the result is wrong (it may
not be obvious to me) and what the correct result should be. Be sure
to use DBD::Informix in the subject line of any email -- thanks!
The minimal test script should preferably:
1. Use the stores database, with empty username and password fields.
If the test needs a particular type of database (eg with
transactions) to demonstrate the problem, alternative convenient
names are 'logged', 'unlogged' and 'mode_ansi'. If you are using
SE, please mention that.
2. Use temporary tables rather than permanent ones.
3. Load just enough data to show the problem.
4. Test every statement that uses a DBI function for success, or
connect using a variant on:
$dbh = DBI->connect('dbi:Informix:stores','','',{RaiseError=>1});
5. Clearly indicate when it fails.
6. Clearly indicate when the test succeeds.
7. The test script should not use DBI->install_driver().
If your test is failing with a core dump, the stack trace may be useful
if it lists function names. The stack trace is not useful if it does
not list them.
The tests which come with DBD::Informix show a variety of ways of using
DBD::Informix. If you need to see how something is used, consider
looking at the test code, including DBD::Informix::TestHarness.
The examples subdirectory contains some simple examples of DBI scripts
for examples sub-directory. Read the examples/README file for more
details.
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REMEMBER IT IS SUPPOSED TO BE FUN!
Jonathan Leffler (jleffler@us.ibm.com)
@(#)$Id: README,v 2011.1 2011/06/12 22:15:50 jleffler Exp $
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Copyright 1994 Tim Bunce
Copyright 1994-96 Alligator Descartes
Copyright 1996-98 Jonathan Leffler
Copyright 1998 Jonathan Leffler
Copyright 1998-99 Jonathan Leffler
Copyright 2000-01 Informix Software Inc
Copyright 2002 IBM
Copyright 2003-11 Jonathan Leffler